1 Get started

We will again use the penguins data included in R.

As always, before you get started with the exercise, make sure that you load the tidyverse

library(tidyverse)

2 Compare the flipper length of penguins using statistical tests

Question: Does the mean flipper length differ between the 3 penguin species?

Do separate comparisons for

  • Gentoo vs. Adelie
  • Gentoo vs. Chinstrap
  • Adelie vs. Chinstrap

Before you start, create a subset of each species as a vector.

For this, you can use the $ operator:

adelie <- filter(penguins, species == "Adelie")$flipper_len
chinstrap <- filter(penguins, species == "Chinstrap")$flipper_len
gentoo <- filter(penguins, species == "Gentoo")$flipper_len

Follow the decision tree for statistical tests:

After you have the test results, visualize the differences in flipper length between species.

You can e.g. choose one of the following plots:

  • Boxplot with notches
  • Mean and standard error of the mean (as mean with errorbar, as barplot, …)

Add a geom_signif() layer to the plot you just created to indicate your test results

2.1 For the fast ones

  • Use a different visualization method than before to show the differences in flipper length between species
  • Change the appearance of the plot (colors, themes, …) from the task